Operating internal combustion engines



July 20, 1937.

OPERATING INTERNAL COMBUSTION ENGIJNES Filed July 21, 1933 M. MUELLER-CUNRADIfr- 0 7,

INVENTORS 7 MART/N MUELLER-CUNRADI MICHAEL OTTO ATTORNEYS-g;

Patented M1 9 v 4 2,087,616

.. s 1 2,087,616 p K I: j OPERATING INTERNALCOMBUSTION -ENGIN ES I, l Martin Mueller Cunradi'andMichael Otto, Lud- I I I vyigshafen-on-thewR-hine, Germany, assignors f to I. G. Farbenindu'strie'"Aktiengesellschaft, Frankfort-on-the-Main, Germany g Application July 21, 1933, Serial No. 681,444

' In Germany Julyv 22, 1932 6"Claims. (01. 44-9) v The-operation ofinternal combustion engines the dangery'of an ignition-in the fuel reservoiris is attended by reason of the ready inflammapractically excluded. i bility of the fuel, by certain dangers which in ve- Hydrogenation products of rubber, ,the so, hicles, especially in-aeroplanes nd-airships, may called hydroerubber, which have different molead to serious results. .iecular sizes depending on their'metho'd of prep- We have now found that-toza great extent, or arat'i'on, are also v'ery suitable; I p I even practically completely-thesaid dangerscan 1 Also tri is'obutylene may. be mentionedwhich be obviated by employing as fuel liquid to solid isnobtainable byvthe actionof approximatelyf'm combustible carbonaceous substances which are percent sulphuric acid on isobutyleneand which 1 10 readily depolymerizable, and splitting the-same a boiling; point of 175 C. and a flashpoint 10 into substances of low molecular weight by heat, of 32" ,6. If this tri -isobutylene be employed as a as for-example with. the aid of the exhaust gases, fuel 'and it .is first led intoa heating chamber and by supplying thefsplitproductsto the comwhich is heated by exhaust gasesyit is depoly bustion chamber. Substances of the said kind 'm'eri ze'd' to give isobutylene and di-isobutylenc j are for example the. polymerization=products of whichare suppliedto, the combustion chamber 5 isobutylene. Isobutylene-n'i'ay be polymerized in in admixture with air. g a various ways, as for'example: with dilute sul- "Furthermore combustible substances of high] phuricacid, preferably at. a temperature bemolecular weight containing-oxygen may beamftween 50- and 100 C.,' or with alkaline bleach ployed. for example diacetone alcohol ing earths and especially with volatile inorganic which' has a flashpoint of about 67C. is suitable. 20

halogen compounds, preferably ata temperature The depolymerization is' preferabiy favoured in between 80 below zero v(1.: and'50 0., .to yield thiscase by the employment of catalysts, as for polymers having a great .variety of "molecular example pumice stone impregnated; with soda 1 sizes and havingtheproperty of being converted lime. 'In the presence of this catalystdiacetone 5 by heating, if desired in the presence of cataalcohol is decomposed into acetone at a temper, lysts, into substances of, low molecular weight, ature of 200 C. V e j Y i. e. into isobutylene or its lower polymers. Pref- The aldol of isobutyraldehyde-is another suiterably a substantial partof products having-a able depolymerizable compound containing oxy} molecular weight below 200 should be formed; gen. ,If this be brought intora decomposition The initial substances to be depolymerized pref chamber heated to about.150 0., it ,is' depoly- 30 I erably have a molecular weight above 400, and merized to give isobutyraldehyde whichjissupw of particular advantage those substancesuare plied to the cylinders. employed which havea molecular weight above Further examples are the polymerization Q1000. But also depolymerizablesubstances havproducts'of styrene which maybe converted v ing a molecular weight less than 400 can be used. into polymers of different molecular sizes in ya- 5 as may be seen from some of the examples givenriouswaysas for example by protracted heating below. preferably to a temperature above 300- C. Very good results are obtained with the high These-substances are also readily depolymerizamolecular polymerization products of isobutyble and may be employed in the same way for 40 lene which are prepared by causing boron fluoroperating internal combustion engines. 5 46 ide to act on isobutylene in the cold. Oily to vis- If catalysts arev employed for the depolymercous solid masses are obtainable depending on ization of the polymerization products, they may the conditions. If these polymerization prod-- be added directly to'the product or they may be ucts be employed as fuel and they are first led introduced into the decomposition'chamber or g into a heating chamber which is heated by exapplied to the inner, surface. In addition to 45 haust gases, preferably to a temperature above those already mentioned a suitable catalyst is 300 (1., they are depolymerized to give their for example phosphoric acid.

lower polymers which are supplied to the com- In order to be able to start the engine in the bustion chamber in admixture with air. When cold state, special means are necessary. For 50 employing strongly viscous or solid substances example an auxiliary fuel,,such as benzine,may. 50

of high molecular weight it is preferable to warm be employed until the engine has warmed up. the same before they are supplied to the split- It is also satisfactory to bring the decomposition ting vessel so that they become mobile or capable chamber to the necessary temperature ,by elecof being pumped. These substances have flashtrlcal heating, heating cartridges or by burning points up to 300 C. so that when using them benzine orpetroleum. 55

Ifhe following example, which is given with reference to the accompanying drawing which shows an arrangement of apparatus according to this invention, will further illustrate the nature of this invention but the invention is not restricted to' this example or the particular arrangement shown.

- Example The storage tank I of a pet'rol engine is ren-- dered capable of being heated by the provision of heating means through which flow the exhaust gases or hot cooling water; instead of a vaporizerf a decomposition chamber 3. is provided which is heated by exhaust gases and to which the fuel is supplied from the storage tank I by means o fa dosing pump 2. From the chamber ,3 he decomposition,products formed pass, while simultaneously sucking in air with which the decomposition products mix, into the cylinders of the engine.

passed through the heating means in the storage tank and'also into the decomposition chamber 3.

A temperature of about C. should be maintained in the storage tank and the inner walls of the decomposition chamber should be at about 350 C. As soon as the said temperatures are attained, the dosing pump 2 is started; this pumps the viscous fuel to the decomposition chamber 3 where it is decomposed into a mixture of isobutylene audits lower "polymers which is-mixed with the air. necessary for combustion and sucked in by the pistons or the cylinders. As soon as this is thecase, the auxiliary'tank is shut off. The engine operates without difficulty,it is found that the fuel so produced has a very high compression value. Theregulation of the supply of fuel is effected by means of va regulating valve 5 which is coupled with a throttle flap 6. i What we claim is:- 1 v 1.- A process for driving an'internal combus tion engine without risks incident to the fuel catching fire whichcomprises using as a source of fuel a polymerizable combustible hydrocarbon substance consisting of hydrogen and carbon only which is bound in the form of a non-explosive polymer thereof having a mean molecular weight of morethan 400 and capable of being depolymer ized upon heating to liberate said substance, passing said polymer to the engine through a heated passage way, thereby depolymerizing said polymer the engine.

catching fire which comprises using as a source of fuel a polymerizable combustible hydrocarbon substance consisting of hydrogen and carbon only which is bound inthe form of a non-explosive polymer thereof having a mean molecular weight of more than 1000 and capableof being depolymerized upon heating to liberate said substance, pass l ing said polymer to the engine through a heated passage way, thereby depolymerizing-said polymer -in said passage way toliberate said combustible substance, and then injecting this substance into 31A process for driving an internal combus:

tion engine without risks incident to the fuel catching fire which comprises passing a combustible. substance selected from the group consists ingiof hydrogenation products of rubber and polymerization products'of isobutylene and styrene through a heated passage way, thereby depolymerizing said substance in said passage way to liberate a product of low molecular weight and then injecting said product into the engine. 4. A process for drivingan internal combustion engine which comprises'depolymerizing bythe action-of heat afrom liquid tosolid combustible hydrocarbon substance consisting of hydrogen and carbon only selected from the'group consist- 1 ingof hydrogenation products of rubber and polymerization products of isobutyleneand styrene, and supplying the depolymerized products to the combustion chamber of said engine.

. 5. ,A process for driving an internal combustion engine. which comprises depolymerizing by the action of heat a fromliquid to solid combustible, depolymerizable hydrocarbon substance consisting of hydrogen andcarbon only having a mean molecular weight of more than 400 in such a manner that. a substantial part i of said; substance is converted 'into'pro'ducts having a" molecular weight below 200, and supplying'the depolymer ized products to the combustion chamber of said engine. i l

6. A process for driving an'intern al combustion-V engine which compris'esdepolymerizing by the action of heat a from liquid to solid combustible, depolymerizable hydrocarbon substance consisting of hydrogen and carbon only having a mean molecular-weight of more than 1000 in such a manner thatJa substantial part of said substance is convertedinto products having a molecular weight below 200, and supplying the depolymerq. ized products to the combustionchamber of said engine. 1 l MARTIN MUELLER-CUNRADL MICHAEL OTTO. 

